As is known, an airplane electronic plate is a plate or shelf placed generally horizontally on a rack in an airplane and which supports electronic apparatus or equipment. For this purpose, the plate usually has slides or grooves to permit installing the electronic apparatus or equipment unit, by sliding along the plate during installation. Since the electronic components inside the apparatus or equipment must be cooled, the plate has an opening for the passage of cooling air which passes over the electric apparatus through openings made in the top and bottom of the cabinet for such apparatus.
For the plate to function properly, it is essential to seal between the bottom of the unit placed on the plate and the plate itself, around the air passage and the cooling air opening, and for this purpose there is provided a continuous or annular seal, supported by the plate and designed to be deformed when the apparatus is put in place and to press itself against the lower surface of the apparatus to seal. Of course this seal must be replaceable.
In addition, the flow of air coming from the cooling system must be regulated and for this purpose a diaphragm or air flow control plate is used, that is, a flow plate having one or more fixed surface openings, the flow plate being placed in the opening of the shelf.
There again, it it necessary not only to provide for interchangeability of this flow plate, but also to seal between the flow plate and the shelf at the connection between the shelf and the flow plate. It is already known to use a single seal element to ensure both the seal against the lower surface of the unit of the apparatus and, on the other hand, the seal between the flow plate and the airplane electronic plate or shelf.
The existing solutions include fastening the seal in the periphery of the opening of the plate by suitable fastening means or a groove made in the seal and into which the edge of the opening of the plate extends, and to fasten the diaphragm or air flow plate by inserting its edge into a groove in the body of the seal located below the seal surface that presses against the lower surface of the unit.
These solutions require the forming of complex seals and a high respect for tolerances, especially at the grooves. Moreover, accidental disengagement of the diaphragm or air flow plate cannot be excluded.